The underbelly of Mrdalsjkull glacier in Iceland, taken a the mouth of a glacial tunnel. The icecap of the glacier covers the active Katla volcano, and the black soot layers of past volcanic eruption

The underbelly of Mrdalsjkull glacier in Iceland, taken a the mouth of a glacial tunnel. The icecap of the glacier covers the active Katla volcano, and the black soot layers of past volcanic eruptions are vividly visible.